An Evaluation of Antimicrobial,Anticancer, Anti-Inflammatory and Antioxidant Activities of Silver Nanoparticles Synthesized from Leaf Extract of Madhuca longifolia Utilizing Quantitative and Qualitative Methods

In the current decade, nanoparticles are synthesized using solvents that are environmentally friendly. A number of nanoparticles have been synthesized at room temperature using water as a solvent, such as gold (Au) and silver (Ag) nanoparticles. As part of nanotechnology, nanoparticles are synthesized through biological processes. Biological methods are the preferred method for the synthesis of inorganic nanoparticles (AgNPs) as a result of their simple and non-hazardous nature. Nanoparticles of silver are used in a variety of applications, including catalysts, spectrally selective coatings for solar absorption, optical objectives, pharmaceutical constituents, and chemical and biological sensing. Antimicrobial agents are among the top uses of silver nanoparticles. In the current study, silver nanoparticles were biologically manufactured through Madhuca longifolia, and their antibacterial activity against pathogenic microorganisms, anticancer, anti-inflammatory, and antioxidant activities were assessed. UV-Vis spectroscopy, XRD (X-ray diffraction), transmission electron microscopy, Zeta Potential, and FTIR were used to characterize silver nanoparticles. The current work describes a cheap and environmentally friendly method to synthesize silver nanoparticles from silver nitrate solution by using plant crude extract as a reducing agent.     

The effect of in situ-formed copolymers on the morphology of reactive poly(phenylene ether)/poly(amide-6) blends

Poly(phenylene ether) (PPE)/poly(amide-6) (PA6) blends are examined in light of the information provided by two-dimensional chromatography and chemorheology. Chromatography provides a snapshot of the blend composition in the finished material, while rheology presents us with a direct insight into the reactions taking place in the melt. Block copolymer formation is chromatographically confirmed for the blends prepared with a coupling agent, but also for the blend prepared without any coupling agent. No co-continuous morphology is observed by scanning electron microscope. Instead, a coarse structure of PPE droplets in the PA6 matrix is obtained for the blend prepared without coupling agent. This is explained by the combined effects of the low viscosity of PA6 and the inherently formed copolymers. The PPE domains are smaller in the blends prepared with the coupling agents. Their size is correlated with the copolymer formation, surface tension, and interphase relaxation time. The data evidence a complex system where reactions resulting in the formation of copolymer via coupling or grafting take place together with the extension of the PPE and condensation growth of the PA6 polymers.     

Determination of Sugar Biomarkers in Methanol Root Extracts of Asparagus Species by High-Performance Thin-Layer Chromatography

JPC – Journal of Planar Chromatography – Modern TLC - This study is a first attempt to present a report about a high-performance thin-layer chromatography (HPTLC)—densitometric...     

<Emphasis Type="Italic">q</Emphasis>- Lupas Kantorovich operators based on Polya distribution

The purpose of the present paper is to introduce a Kantorovich modification of the q-analogue of the Stancu operators defined by Nowak (J Math Anal Appl 350:50–55, 2009). We study a local and a direct approximation theorem by means of the Ditzian–Totik modulus of smoothness. Further A-statistical convergence properties of these operators are investigated. Next, a bivariate generalization of these operators is introduced and its rate of convergence is discussed with the aid of the partial and complete modulus of continuity and the Peetre‘s K-functional.     

On $\Psi$-projective expansion, quasi partial metrics aggregation with an application

In the present article, the notion of expansion between quasi partial metric spaces through aggregation is defined. With the help of aggregation functions, the concept of projective $\Psi$-expansion is introduced and some fixed point results are obtained through this notion. Furthermore, sufficient conditions are provided to characterize aggregation function and to ensure the existence and uniqueness of fixed point. All the results presented in this paper are new and an application to asymptotic complexity analysis is also given after the results.     

Metal and organo-complex promoted synthesis of fused five-membered O-heterocycles

Abstract

One of the highly emerging and an important aspect of organic chemistry is the metal and organo-complex promoted synthesis of the heterocycles. The methodologies used earlier for its synthesis were less approachable to the organic chemist due to their high cost, highly sophisticated instrumentation and problematic methods. For both stereoselective and regioselective synthesis of fused five-membered O-containing heterocycles, cyclic reactions that are metal and organo-complex promoted have been known to be very efficient. The present review article covers the different applications of metals and organo-complexes in the formation of fused five-membered oxygen containing fused heterocycles. The fascinating research that has been done in this area is enclosed in this review.     

Synthesis of amphiphilic poly(N‐vinylcaprolactam) using ATRP protocol and antibacterial study of its silver nanocomposite

Atom transfer radical polymerization (ATRP) of N‐vinylcaprolactam (NVCL) was studied by uisng ethyl‐2‐bromoisobutyrate (EIB) as initiator in 1,4‐dioxane. It led to controlled radical polymerization of NVCL, with the molecular weight increased along with the conversion of monomer and a relatively narrow molecular weight distribution could be obtained, as determined by gel permeation chromatography. ¹H NMR showed that the major population of poly(N‐vinylcaprolactam) (PVCL) retained the chain‐end functional group. The living nature of the ATRP for NVCL was confirmed by the experiments of PVCL chain extension. PVCL was further investigated for its ability to form micelles in aqueous media. Self‐assembling of the amphiphilic PVCL leads to the formation of their micellar aggregates in aqueous media which was confirmed by transmission electron microscope. The critical micelle concentration value was calculated from the photophysical changes of Pyrene‐1‐Carboxaldehyde by UV absorption studies and was found to be 0.0320 mg/mL. The polymer nanocomposite was synthesized and examined in view of antibacterial effect against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Proteus mirabilis, and Klebsiella pneumonae. It was found that polymer nanocomposite possess strong antibacterial activity against Enterococcus faecalis with minimum inhibitory concentration value of 32 μg/mL. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Ultra low density and highly crosslinked biocompatible shape memory polyurethane foams

We report the development of highly chemically crosslinked, ultra low density (～0.015 g/cc) polyurethane shape memory foams synthesized from symmetrical, low molecular weight, and branched hydroxyl monomers. Sharp single glass transitions (T_g) customizable in the functional range of 45–70 °C were achieved. Thermomechanical testing confirmed shape memory behavior with 97–98% shape recovery over repeated cycles, a glassy storage modulus of 200–300 kPa, and recovery stresses of 5–15 kPa. Shape holding tests under constrained storage above the T_g showed stable shape memory. A high volume expansion of up to 70 times was seen on actuation of these foams from a fully compressed state. Low in vitro cell activation induced by the foam compared with controls demonstrates low acute bio‐reactivity. We believe these porous polymeric scaffolds constitute an important class of novel smart biomaterials with multiple potential applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012